ThinkPad 760XD black screen

[Q91]

Hi, I'm new and I've got a problem with an old 760Xd I found in my attic. It has Win95. When I start it, nothing appears on the screen, but I can see it's running, there's some HDD work. After some time (maybe 1/2 or 1h later), I can hear normal noise in it. Even if I plug it on an external monitor, nothin'...

The battery is fully charged and the thinkpad keeps running when I unplug it from the sector. The problem is just the black screen.
Does someone know what's going on here ??
Thx.

[ozzymud]

Ok, a few things...

Even if I plug it on an external monitor, nothin'...

When the external monitor was plugged in, did you press Fn+F7 to switch to it? On my 760's, If I have the external plugged in at poweron, the 760 only displays to the external, nothing happens if I plug it in with the 760 already on until i press Fn+F7, then it switches between 3 modes:

1. external only
2. both
3. 760 only

Shine a flashlight at the laptop screen while it is on, is it really black? Or can you make out faint images on it? (If you can see "something", backlight inverter board is dead or bad connection)... if you see something... this is the order of suspision I go with when diagnosing (fortunately i have several of each model todo swap with known good tests)...

• Reseat the LCD connectors. *
• Inverter Card *
• Video Card
• LCD Assembly **
• DC/DC Card
• CPU Card ***
• Systemboard ***

* These are the most likely candidates IMO, the flashlight test should diagnose these easily
** This is the most unlikely candidate IMO, these screens are bulletproof, I have one with HUNDREDS of dead pixels, still works and actually quite viewable
*** I would doubt these items as it sounds like your system is still booting

The normal noise you hear is the fan most likely (mine usually starts after the same timeframe depending on ambiant conditions)

[Q91]

Thanks for answering

did you press Fn+F7 to switch to it? On my 760's, If I have the external plugged in at poweron, the 760 only displays to the external, nothing happens if I plug it in with the 760 already on until i press Fn+F7

Yes, I tried it several time.

• Reseat the LCD connectors. *
• Inverter Card *
• Video Card
• LCD Assembly **
• DC/DC Card
• CPU Card ***
• Systemboard ***

How can I get to those LCD connectors ? By the way, I managed to take away all the componants (HDD, CD, battery,...), but not the big black part behind them...

The normal noise you hear is the fan most likely (mine usually starts after the same timeframe depending on ambiant conditions)

That's right.

[ozzymud]

Pictures of disassembly are in Hardware Maintenance Manual
Volume 3. Not sure what "black part" you mean. If you mean the aluminum upper shield with black/yellow sticker... it is attached with 4 screws (pictured on page 403 of the manual)

So, you cant see ANY ghost image at all when powered up using a flashlight? But seeing how you cant switch to the external, it prolly aint the backlight.

Here's hoping whoever put it in the attic had it apart and didn't reconnect something on reassembly

If not, video card, DC to DC card... or motherboard

[Q91]

That's what I meant :

http://img861.imageshack.us/img861/4684/sansreyf.png

Of course, I pulled the screws away, but I couldn't take that off...
Well, when I turn the pc on, I can see that the screen's going a little brighter, but no more.

I'm also afraid for the video card

Thank you for the link, btw

Admin edit: Removed HUGE (2.5MB) inline image. Please LINK to photos/images if you can't sized them <50KB.

[ozzymud]

you need the screen and keyboard off as well... there are more screws under the screen/keyboard hinge area

(Note 2nd screw at top might need one more behind this from backside removed to clear the screw)
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